.page-about {
  --about-gap: 32px;
  --about-wrap-pad: 20px;
  background: var(--cloud);
  color: var(--graphite);
  overflow-x: hidden;
}

.page-about .wrap {
  padding-left: var(--about-wrap-pad);
  padding-right: var(--about-wrap-pad);
  margin-left: auto;
  margin-right: auto;
  max-width: var(--wrap);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  background: var(--deep);
  color: var(--cloud);
  padding: calc(var(--header-h) + 36px) 0 56px;
  overflow: hidden;
  border-bottom-left-radius: 40px;
  border-bottom-right-radius: 40px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -18%;
  right: -22%;
  width: 62%;
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background: radial-gradient(circle at 40% 40%, rgba(232, 163, 61, .28), rgba(232, 163, 61, 0) 66%);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  bottom: -30%;
  left: -12%;
  width: 44%;
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background: radial-gradient(circle at 55% 45%, rgba(41, 199, 183, .22), rgba(41, 199, 183, 0) 68%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .crumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: .875rem;
  color: rgba(247, 244, 238, .6);
  margin-bottom: 30px;
}

.page-about .about-hero .crumbs a {
  color: rgba(247, 244, 238, .78);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .about-hero .crumbs a:hover {
  color: var(--teal);
  border-bottom-color: var(--teal);
}

.page-about .about-hero .crumbs__sep {
  color: rgba(247, 244, 238, .34);
}

.page-about .about-hero .eyebrow {
  font-family: var(--font-mono);
  font-size: .8125rem;
  letter-spacing: .18em;
  color: var(--gold);
  margin: 0 0 18px;
}

.page-about .about-hero h1 {
  font-size: clamp(1.9rem, 6.2vw, 3.6rem);
  line-height: 1.2;
  letter-spacing: .02em;
  font-weight: 900;
  margin: 0 0 22px;
  max-width: 19em;
}

.page-about .about-hero__lede {
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(247, 244, 238, .8);
  max-width: 40em;
  margin: 0 0 40px;
}

.page-about .about-hero__facts {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px 18px;
}

.page-about .about-hero__facts li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding-left: 14px;
  border-left: 1px solid var(--line-gold);
}

.page-about .about-hero__num {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 600;
  letter-spacing: .04em;
  color: var(--gold-light);
  line-height: 1.1;
}

.page-about .about-hero__label {
  font-size: .8125rem;
  line-height: 1.5;
  color: rgba(247, 244, 238, .64);
}

/* ---------- 章节索引 ---------- */

.page-about .about-index {
  position: sticky;
  top: var(--header-h);
  z-index: 20;
  background: rgba(247, 244, 238, .95);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(10px);
}

.page-about .about-index__inner {
  padding-top: 12px;
  padding-bottom: 12px;
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 2px 0 6px;
  display: flex;
  gap: 10px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
  scroll-snap-type: x proximity;
}

.page-about .about-index__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-index__list > li {
  scroll-snap-align: start;
  flex: 0 0 auto;
}

.page-about .sec-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border-radius: 999px;
  border: 1px solid var(--line);
  font-size: .875rem;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: color .24s var(--ease), border-color .24s var(--ease), background-color .24s var(--ease);
}

.page-about .sec-link__num {
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .08em;
  color: var(--gold);
}

.page-about .sec-link:hover {
  border-color: var(--gold);
  color: var(--graphite);
}

.page-about .sec-link.is-active,
.page-about .sec-link[aria-current="true"] {
  background: var(--deep);
  border-color: var(--deep);
  color: var(--cloud);
}

.page-about .sec-link.is-active .sec-link__num,
.page-about .sec-link[aria-current="true"] .sec-link__num {
  color: var(--teal);
}

/* ---------- 章节骨架 ---------- */

.page-about .about-chapter {
  position: relative;
  padding: 56px 0;
  scroll-margin-top: calc(var(--header-h) + 72px);
}

.page-about .about-chapter + .about-chapter {
  border-top: 1px solid var(--line);
}

.page-about .about-chapter--dark,
.page-about .about-chapter--deep {
  background: var(--deep);
  color: var(--cloud);
  border-top-color: transparent;
}

.page-about .about-chapter--deep {
  background: var(--deep-dark);
}

.page-about .about-chapter--dark + .about-chapter,
.page-about .about-chapter--deep + .about-chapter {
  border-top-color: transparent;
}

.page-about .about-chapter__grid {
  display: grid;
  gap: var(--about-gap);
}

.page-about .about-chapter__side {
  position: relative;
  padding-top: 4px;
}

.page-about .sec-num {
  display: block;
  font-family: var(--font-serif);
  font-size: clamp(3rem, 12vw, 4.6rem);
  line-height: .92;
  letter-spacing: .04em;
  color: var(--gold);
  margin-bottom: 14px;
}

.page-about .about-chapter__side h2 {
  font-size: clamp(1.35rem, 4.6vw, 2rem);
  line-height: 1.35;
  font-weight: 900;
  letter-spacing: .02em;
  margin: 0 0 14px;
  max-width: 15em;
}

.page-about .about-chapter__lede {
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--mist);
  margin: 0;
  max-width: 24em;
}

.page-about .about-chapter--dark .about-chapter__lede,
.page-about .about-chapter--deep .about-chapter__lede {
  color: rgba(247, 244, 238, .62);
}

.page-about .about-chapter__intro {
  font-size: 1rem;
  line-height: 1.8;
  margin: 0 0 26px;
  max-width: 40em;
}

.page-about .about-chapter__note {
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--mist);
  margin: 22px 0 0;
  padding-left: 16px;
  border-left: 2px solid var(--line-gold);
  max-width: 40em;
}

.page-about .about-chapter--dark .about-chapter__note,
.page-about .about-chapter--deep .about-chapter__note {
  color: rgba(247, 244, 238, .66);
}

/* ---------- 列表 ---------- */

.page-about .about-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .about-list > li {
  padding: 20px 0 20px 18px;
  border-bottom: 1px solid var(--line);
  position: relative;
  transition: padding-left .24s var(--ease);
}

.page-about .about-list > li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 24px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--gold);
  opacity: .55;
  transition: opacity .24s var(--ease), transform .24s var(--ease);
}

.page-about .about-list > li:hover {
  padding-left: 24px;
}

.page-about .about-list > li:hover::before {
  opacity: 1;
  transform: scale(1.35);
}

.page-about .about-list h3 {
  font-size: 1.0625rem;
  font-weight: 800;
  letter-spacing: .01em;
  margin: 0 0 8px;
}

.page-about .about-list p {
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--mist);
  margin: 0;
  max-width: 38em;
}

.page-about .about-list a {
  color: var(--graphite);
  text-decoration: none;
  border-bottom: 1px solid var(--gold);
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .about-list a:hover {
  color: var(--teal);
  border-bottom-color: var(--teal);
}

.page-about .about-list--light {
  border-top-color: var(--line-light);
}

.page-about .about-list--light > li {
  border-bottom-color: var(--line-light);
}

.page-about .about-list--light p {
  color: rgba(247, 244, 238, .68);
}

.page-about .about-list--light a {
  color: var(--cloud);
}

/* ---------- 数据块 ---------- */

.page-about .fact-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-light);
  border: 1px solid var(--line-light);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.page-about .fact {
  position: relative;
  background: var(--deep);
  padding: 20px 18px 32px;
  outline: none;
  transition: background-color .24s var(--ease);
}

.page-about .fact:hover,
.page-about .fact:focus-visible {
  background: #143354;
}

.page-about .fact:focus-visible {
  box-shadow: inset 0 0 0 2px var(--teal);
}

.page-about .fact__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.625rem;
  font-weight: 600;
  letter-spacing: .04em;
  line-height: 1.15;
  color: var(--gold-light);
  margin-bottom: 6px;
}

.page-about .fact__label {
  display: block;
  font-size: .875rem;
  line-height: 1.6;
  color: rgba(247, 244, 238, .78);
}

.page-about .fact__note {
  position: absolute;
  left: 18px;
  right: 18px;
  bottom: 10px;
  font-size: .75rem;
  line-height: 1.4;
  color: rgba(247, 244, 238, 0);
  transform: translateY(5px);
  transition: color .24s var(--ease), transform .24s var(--ease);
  pointer-events: none;
}

.page-about .fact:hover .fact__note,
.page-about .fact:focus-visible .fact__note {
  color: var(--teal);
  transform: translateY(0);
}

/* ---------- 团队 ---------- */

.page-about .team-rows {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .team-row {
  display: grid;
  grid-template-columns: 5.2em 1fr 2.4em;
  align-items: center;
  gap: 14px;
  padding: 15px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .team-row__name {
  font-size: .9375rem;
  font-weight: 700;
  color: var(--graphite);
}

.page-about .team-row__track {
  display: block;
  height: 6px;
  border-radius: 999px;
  background: rgba(107, 124, 147, .18);
  overflow: hidden;
}

.page-about .team-row__track i {
  display: block;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--gold), var(--gold-light));
  transition: width .5s var(--ease);
}

.page-about .team-row__num {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 600;
  color: var(--gold);
  text-align: right;
}

/* ---------- 迭代时间轴 ---------- */

.page-about .iter-figure {
  margin: 0 0 26px;
  padding: 18px 14px 12px;
  background: rgba(8, 26, 46, .5);
  border: 1px solid var(--line-light);
  border-radius: var(--radius-lg);
}

.page-about .iter-map {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .iter-map__dots circle {
  transition: r .24s var(--ease), fill .24s var(--ease);
}

.page-about .iter-map__dots circle:hover {
  r: 11;
  fill: var(--teal);
}

.page-about .iter-map__tag {
  font-family: var(--font-mono);
  font-size: 22px;
  letter-spacing: .08em;
  fill: var(--gold-light);
}

.page-about .iter-figure__caption {
  margin: 12px 2px 0;
  font-size: .8125rem;
  line-height: 1.7;
  color: rgba(247, 244, 238, .6);
}

/* ---------- 媒体 ---------- */

.page-about .about-media {
  margin: 26px 0 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: rgba(107, 124, 147, .1);
}

.page-about .about-media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-media .media__caption {
  padding: 12px 16px 14px;
  font-size: .8125rem;
  line-height: 1.7;
  color: var(--mist);
  margin: 0;
}

.page-about .about-chapter--dark .about-media .media__caption,
.page-about .about-chapter--deep .about-media .media__caption {
  color: rgba(247, 244, 238, .6);
}

/* ---------- 行动区 ---------- */

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-cta .btn {
  flex: 0 0 auto;
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about {
    --about-wrap-pad: 32px;
  }

  .page-about .about-hero {
    padding: calc(var(--header-h) + 56px) 0 84px;
  }

  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .fact-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .fact {
    padding: 24px 22px 36px;
  }

  .page-about .fact__note {
    left: 22px;
    right: 22px;
  }

  .page-about .about-chapter {
    padding: 76px 0;
  }
}

@media (min-width: 900px) {
  .page-about {
    --about-gap: 56px;
  }

  .page-about .about-chapter__grid {
    grid-template-columns: 1fr;
  }

  .page-about .about-chapter__grid--a {
    grid-template-columns: 4fr 7fr;
  }

  .page-about .about-chapter__grid--b {
    grid-template-columns: 6fr 5fr;
  }

  .page-about .about-chapter__side {
    position: sticky;
    top: calc(var(--header-h) + 86px);
    align-self: start;
  }

  .page-about .about-chapter {
    padding: 96px 0;
  }

  .page-about .about-chapter__intro {
    font-size: 1.0625rem;
  }
}

@media (min-width: 1200px) {
  .page-about .about-chapter__grid--a {
    grid-template-columns: 4fr 7fr;
    column-gap: 72px;
  }

  .page-about .about-chapter__grid--b {
    grid-template-columns: 6fr 5fr;
    column-gap: 72px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-list > li,
  .page-about .about-list > li::before,
  .page-about .fact,
  .page-about .fact__note,
  .page-about .sec-link,
  .page-about .iter-map__dots circle,
  .page-about .team-row__track i {
    transition: none;
  }
}